1. Field of the Invention
The present invention relates to a vehicle control system.
2. Description of the Related Art
The combination, in a vehicle, of a navigation apparatus and suspension control apparatus to enable control of the suspension in accordance with road condition data provided by the navigation apparatus is disclosed, for example, in Japanese Patent Application Publication (“kokai”) No. JP-A-2000-318634. In such a vehicle control system, changes in level of the toad stored in a database are used to control the rigidity of the suspension.
However, in the conventional suspension control apparatus described in kokai 2000-318634 wherein the suspension is softened when passing over level changes, e.g. bumps, when the vehicle speed is high, it has been possible to provide sufficient riding comfort. The vertical acceleration that occurs when the vehicle passes over a level change is determined by the magnitude (size) of the level change and the vehicle speed, and thus, for the same level change, the vertical acceleration becomes higher as the vehicle speed becomes higher. In addition, because there are limits to the range in which the rigidity of the suspension can be controlled, even when the suspension is made as soft as possible, when the vehicle speed is high, it is possible to suitably absorb this vertical acceleration, and the riding comfort suffers.